关于混凝土废弃物岩尾回填填物的机械性能和损伤特征的研究
Guan Chen1, Nan Yao2, Yicheng Ye1,3
1School of Resources and Environmental Engineering, Wuhan University of Science and Technology, Wuhan, 430081, China.
Environmental science and pollution research international
|September 2, 2023
概括
这项研究优化了使用矿山废物岩石和尾矿的水泥填充. 理想的混合物,60%的废岩和1:4的水泥砂比,增强了压力强度,并为更安全的采矿操作提供了损坏模型.
科学领域:
- 地质技术工程 地质技术工程
- 材料科学 材料科学 材料科学
- 环境工程 环境工程
背景情况:
- 矿山固体废物,包括尾矿和废岩,造成了重大处置挑战.
- 用水泥填充是管理矿山废物和填补地下空洞的可行策略.
研究的目的:
- 研究废岩含量和水泥砂比对水泥填充材料性能的影响.
- 确定最佳的混合物参数,以最大限度地提高压力强度,并了解故障机制.
- 为了建立酸盐岩石工程中水泥填充的损害构成模型.
主要方法:
- 单因素多层次实验设计.
- 填充泥属性的分析:流动性和出血率.
- 单轴压缩试验用于评估压力强度和故障模式.
- 微结构分析 (水化产品) 和声辐射 (AE) 测试.
- 开发一个损害构成模型.
主要成果:
- 流动性和出血率对废岩的含量敏感,而压力强度在60%的废岩和1:4的水泥砂比率上达到顶峰.
- 废岩含量增加导致更大的接口故障区域,复杂的裂传播和更高的AE数量.
- 微观结构分析显示,由于丰富的酸盐水合 (C-S-H) 凝,酸 (AFt) 和氧化 (Ca(OH) 的存在,填充量更密,压力强度更高2).
结论:
- 高强度水泥填充的最佳成分是60%的废岩含量,水泥和砂的比例为1:4.
- 了解组成,微观结构和机械性能之间的关系对于有效的矿山填充至关重要.
- 开发的损害构成模型为酸盐岩填充工程的设计和安全生产提供了宝贵的指导.
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